However, investigation into just what these objects may have been have pretty conclusively demonstrated the vast majority of these reports have prosaic explanations such as hoaxes, hysteria, or misidentified natural or man-made objects, much to the chagrin of the UFO community.
While many dismiss such explanations as simplistic attempts to skirt the issue or, worse, a carefully contrived and orchestrated effort at debunking the entire phenomena, the fact is that many, if not most, UFOs can usually be explained away.
As such, it's important we examine each of the many explanations offered, if only in an effort to better appreciate the difficulties investigators frequently face when looking at the phenomena from a scientific perspective, compelling me to create my list-in no particular order-of the top ten alternative explanations usually given to explain UFOs.
10. The planet Venus
It's no coincidence that UFO reports go up sharply whenever Venus makes an especially bright appearance in the night sky, so this explanation is not as far-fetched as it seems.
Under the proper conditions, Venus can be among the brightest objects in the sky-particularly on a moonless night-and has even been known to be visible in the daytime under the proper conditions, making it a frequent explanation for many a mysterious "bright light in the sky."
For those already predisposed towards accepting any unusual light in the sky as a potential close encounter, Venus makes an excellent candidate for being a UFO-especially when it is seen low on the horizon from a moving automobile (when it can appear to be "chasing them"), or on a partly cloudy night when it will seem to abruptly appear and disappear as fast-moving clouds obscure it from view.
Additionally, it can be extremely difficult to convince people that the bright light in the sky they saw was merely sunlight reflecting off a nearby planet, largely because of the natural human reluctance to admit error as well as the trauma such an experience can sometimes induce.
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